I wonder how a big donaldson would work? You should have plenty of room to shoehorn a 4ft + muffler in there.
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01.5 QC ETH/DEE 4x4
DDP 4's, Smarty, Super B, Fass II/Vulcan, Hol'd Scotty II, Con ofe, 5" exhaust, Autometer Boost, Pyro, FP, and Trans 404/872